When running Qt Creator (based on Qt 5.7.1 and the MinGW edition), the following is not populated in the .pro.user file, and simply has nothing outside of the tags:

<value type="QString" key="Qt4ProjectManager.Qt4RunConfiguration.UserWorkingDirectory.default"></value>

This affects the programs we are running, which launch subprograms.

If I manually enter that key into the .pro.user file, everything runs fine.

I can also fix the issue by selecting Projects in the left hand window, then checking "Run in Terminal." If I run the program once in the terminal, and then de-select the "Run in Terminal Checkbox," the program will run fine from within Qt Creator (and the key is populated in the XML file).